An insulation film is used to isolate various electronic devices or components to avoid malfunction caused by short-circuiting, breakdown or the like between the electronic devices or components, or electronic elements in the electronic devices or components, and reduce the risk of catching fire of the electronic devices or components so as to guarantee normal operation of various electronic elements. For example, the insulation film is placed between a printed circuit board (PCB) containing various circuits and a metallic housing such as an aluminum or copper housing for preventing EMI (electromagnetic interference) to prevent problems such as shortcricuiting caused by contact between the various elements on the PCB and the metallic housing. In order to use the insulation film, the insulation film is required to have properties such as flame retardance and resistance against long-term high temperature. Furthermore, specific indices for the requirements for these properties of the insulation film vary with different requirements for insulation.
Since the raw material of PC and PET have good puncture resistance property, insulation films made of PC or PET are widely used. However, the folding endurance property of PC and PET is not good, and therefore, the PC and PET will be torn when being folded.
Therefore, it is desired to produce a insulation film having both good puncture strength and good folding endurance property.